1. Field of the Invention
The present invention relates to securing of heat sinks to electronic devices, and particularly to clips of heat sink clip assemblies that have coil structures which can be configured to provide suitable pressing force acting on a heat sink.
2. Related Art
Advances in microelectronics technology have resulted in electronic devices which process signals and data at unprecedented high speeds. During operation of many contemporary electronic devices such as central processing units (CPUs), large amounts of heat are produced. The heat must be efficiently removed, to prevent the system from becoming unstable or being damaged. Heat sink assemblies are frequently used to dissipate heat from these electronic devices.
A clip is often used to attach a heat sink to an electronic device. The clip is usually integrally formed from plastic material, or made by bending a spring steel wire. Examples of such heat sink clips are disclosed in U.S. Pat. Nos. 5,464,054, 5,640,305 and 6,105,215. Mass-producing plastic clips requires developing a set of dies over a relatively long period of time. This results in high development costs. Once the dies are developed, it is difficult to change a required configuration of the clips. Furthermore, configurations of plastic clips are limited in scope. Oftentimes, it is impossible to obtain a configuration of a plastic clip that enables the clip to avoid interference with other components inside a computer. Wire clips can be configured to avoid such interference. However, it is problematic to obtain spring steel wire with a suitable hardness, having regard to the conflicting objectives of providing sufficient pressing force and providing sufficient resiliency for manual operation.
Thus, an improved heat sink clip assembly which overcomes the above problems is desired.
Accordingly, an object of the present invention is to provide a heat sink clip assembly having coiled structures which can be easily configured to meet the pressing force requirements of any particular application.
Another object of the present invention is to provide a heat sink clip assembly which readily and securely attaches a heat sink to an electronic device.
To achieve the above-mentioned objects, a heat sink clip assembly of the present invention is used to attach a heat sink to a CPU which is mounted to a motherboard. The heat sink clip assembly comprises a rigid shaft and two wire clips. The rigid shaft comprises a pressing section for pressing the heat sink, two engaging sections at opposite ends of the pressing section, and two stop sections at outmost ends of the engaging sections. A diameter of the engaging sections is less than diameters of the pressing section and the stop sections. Each wire clip has a coiled portion, and two spring arms extending from opposite ends of the coiled portion. Each spring arm extends perpendicularly to a central axis of the coiled portion. A hook is formed at a distal end of each spring arm, for engaging with a corresponding through hole of the motherboard. The heat sink is thereby attached to the motherboard.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of a preferred embodiment of the present invention together with the attached drawings, in which: